Emmanuel Akakabota

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8 years, 9 months ago.

No output

Hi Wayne. I'm trying to use your code to generate three phase sine waves from my Mbed LPC1768. The voltage output on pins 21, 22 and 23 are at a steady 2.2 V. I wonder what the problem might be, as your code seems logical.

Question relating to:

Last updated: 28 Nov 2010
Uses trigonometry to produce high quality 3 phase sinewave output waveworms on the PWM. Tested from 30 to 100Hz at 10kHz modulation. Changes frequency glitch free. Amplitude is scalable. Could … control, induction, invertor, motor, phase

1 Answer

Wayne McLachlan
8 years, 9 months ago.

Hi, I'm glad to see it's of use to someone. Can you please sketch the circuit you're feeding it to. Perhaps there's an impedance problem?

What are you using it for?

Regards, W.

I'm working on a three phase inverter using dead-band current control. I require a controllable (amplitude and frequency) three phase sine wave output to be used as current reference. After compiling the code I only tried to view the outputs of the PWM out pins 21, 22 and 23 on the oscilloscope. As yet, I have not fed it to any circuit, just the oscilloscope probes for viewing. The steady 2.2 V is shown across the three pins, as well as across all the other PWM out pins.

posted by Emmanuel Akakabota 11 Aug 2015

Seems you have been very busy or don't visit this site often. Do you think I can get an email address through which I can contact you?

posted by Emmanuel Akakabota 17 Aug 2015